docs: def _get_seal_key_ntlm1(negotiate_flags, exported_session_key):
      """
      3.4.5.3 SEALKEY
      Calculates the seal_key used to seal (encrypt) messages. This for authentication where
      NTLMSSP_NEGOTIATE_EXTENDED_SESSIONSECURITY has not been negotiated. Will weaken the keys
      if NTLMSSP_NEGOTIATE_56 is not negotiated it will default to the 40-bit key
  
      @param negotiate_flags: The negotiate_flags structure sent by the server
      @param exported_session_key: A 128-bit session key used to derive signing and sealing keys
      @return seal_key: Key used to seal messages
      """
      if negotiate_flags & NegotiateFlags.NTLMSSP_NEGOTIATE_56:
          seal_key = exported_session_key[:7] + binascii.unhexlify('a0')
      else:
          seal_key = exported_session_key[:5] + binascii.unhexlify('e538b0')
  
      return seal_key